Jurgen Klopp has explained his decision not to use Daniel Sturridge in Liverpool's 1-0 defeat at Villarreal on Thursday, stressing that his focus was on maintaining stability.

Sturridge had been expected to lead the line for the Europa League semifinal first leg at El Madrigal in the absence of the injured Divock Origi, but Klopp opted to use Roberto Firmino as the focus of his attack.

Speaking ahead of the match, Klopp had told BT Sport it was "a very difficult decision" and said: "I thought about a lot of things and at the end I decided for a little bit more stability.

"In a 4-3-3 we didn't play with Daniel until now, so we thought for today -- this 4-3-3, 4-5-1, sometimes a diamond, this very flexible style -- it makes sense that the players played together before and that's why we decided for this lineup."

Sturridge remained on the bench throughout the match, with Philippe Coutinho, who had to come off at half-time due to illness, replaced by winger Jordon Ibe.

Jurgen Klopp said Daniel Sturridge was unfamiliar with his 'flexible' formation against Villarreal.

Christian Benteke came on for Firmino in the 90th minute, shortly before Adrian Lopez scored the winner through a Villarreal counter-attack, but Klopp said after the match that the Belgian had been introduced for defensive reasons.

"We had one or two situations in defence with set pieces and Christian can help us in this situation, and that was the only reason," he told his postmatch news conference. "It was not really for attacking, but we had this moment and I thought it wasn't a bad idea [to bring Benteke on]. We had no luck."

Liverpool now need to secure victory at Anfield if they are to progress and Klopp has vowed to "throw the kitchen sink" at Villarreal in next Thursday's second leg.

"It is not a moment for disappointment," he told BBC Sport. "If the players want to be angry for 10 minutes then do it and move on.

"To be honest it is the first leg. My first thought was: 'Sorry, but it is not over, you have to come to Anfield too and we will be ready.'"

He added: "If you go out in the semis, then do so kicking and screaming."

England international Sturridge has suffered with a succession of injuries since playing a starring role in Liverpool's title challenge in 2013-14 but has been a regular fixture in the squad since returning to action in February.